As a device for absorbing harmful or helpful gas, a gas-liquid contacting device using an absorbent is known. In chemical plants, in order to increase the absorption efficiency of exhausted gas such as carbon dioxide (CO2), for example, a cylindrical or rectangular absorber is mainly used and a gas-liquid contacting plate is disposed inside a tower to increase the contact area of gas and the absorbent. In general, it is known that gas-liquid contacting performance depends on the total surface area of liquid films. In order to obtain high gas-liquid contacting performance, it is preferable that liquid be widely spread out on the surface of the gas-liquid contacting plate as much as possible. The wide spread-out of liquid represents excellent wettability. As a material of the gas-liquid contacting plate, a metal material is mainly used.
Gas-liquid contacting plates are disposed inside a container of the absorber to spray the absorbent through nozzles. However, it is difficult for the absorbent to be evenly sprayed inside the container. In addition, it is difficult for wettability to be evenly distributed for all the surfaces of a plurality of the gas-liquid contacting plates, which is provided inside the container. In addition, when the gas-liquid contacting plate is made of metal, the total weight of a gas-liquid contacting tower increases and thus there is a problem in that the sizes of structural parts supporting the gas-liquid contacting tower increase.
On the other hand, as the material of the gas-liquid contacting plate instead of a metal, for example, a polymeric material such as resin may be considered. Though the polymeric material has a light weight, excellent workability performance, a chemical resistance property, and an inexpensive cost, most of the polymeric material used as industrial materials is hydrophobic, and thereby there is a problem in that it is difficult to obtain wettability described above.
In recent years, so-called hydrophilic polymers, which are polymeric materials and have hydrophilicity, have been known. When a hydrophilic polymer is used as a material of the gas-liquid contacting plate, the weight is light, workability is superior, and further, the above-described wettability is also easily obtained. However, there are problems in that the hydrophilic polymers are generally expensive compared to hydrophobic polymer materials and the moldability into a compact such as a film is low. In addition, it is known that the hydrophilic polymers have a problem in that they absorb moisture when being in contact with water and thus the strength thereof deteriorates, which is problematic.
Herein, the gas-liquid contacting plate having excellent workability, inexpensive cost and hydrophilicity at a bottom portion of a concave portion in which wettability is spread out in an width direction of the gas-liquid contacting plate is proposed (Patent Literature 1).